Automatic hammer



(5.1.. KOLLOCK AND vR. P. MARTIN.

AUTOMATIC HAMMER.

APPLICATION FILED ocr. 5. -1911.

Patented July 22, 1919.

EIII

INVENTOH Afro/INEI GEORGE iL. KoLLoox AND ROBERT 1 MARTIN, or SEATTLE, WASHINGTON, AssrGNoRs" l'.lO UNIVERSAL HAMMER COMPANY, 0F SEATTLE, WASHINGTON, A'CORYPORATIQN OF WASHINGTON.

To all whom'zt may concern.'

Be it known that we, GEORGE L. KoLLooK, a citizen of the United States, residing at Seattle, in the county of King and State of Washington, and ROBERT P. MARTIN, a citizen of the United States, residing at Seattle, in the county of-Kingand State of Washington, have invented certain new and useful Improvements in Automatic Hammers, the following being a full, clear, and -eXact disclosure of the one form of our invention which. we at present deem preferable.

. For a detailed description of the present form of our invention, reference may be had to the following specification and to the accompanying drawing forming a part thereof, wherein Figure 1 is a deviceg- Fig. 2 is asimilar section of the hammer part with the cam in elevation;

Fig. 3 is a transverse section on the line 3 3 of Fig. 1;

Fig. 4 is a similar section on the line 4 4 of Fig. 1;

Figs. 5 and 6 show details.

Our invention relates to a spring-actuated hammer, wherein the spring 1s periodically put under tension by means of an electric motor and periodically released in order to give the hammer an impact pressure corresponding to the force stored up in the spring by its previous tensioning. The electric motor has a continuous rotary motion which is converted into the periodic movement involved in the aforesaid tensioning of the spring, by the agency of a cam which is rotated by the motor and acts upon the spring through one or more inclined Vsurfaces of a saw tooth form, which are engaged by the device which act uponthe spring. The saidengagin devices are rollers which ride upon the inc ined surfaces ofthe cam, putlongitudinal section of our ting the s ring under tension a's they travelv u the sai surfaces, and releasing Vthe spring W en they drop oi the saw tooth polnts. One purpose of our inventionis to produce .a practicable form of portable tool with the armature shaft of the motor substantially in line with the reciprocatin ,hammer element or striker. This not o y gives a compact constructionbut also utilizes the weight .of the -motor as an abutment to absorb the v. reactionlcf the blow or impact.l `We also surface of the disk L is AUTOMATIC HAMMER.

provide against side strains and against unbalanced strains on opposite sides of the axis of the tool.

Referring to-the drawing, A represents one section of a cylindrical longitudmal casing, which serves/at the same time as the yoke of the motor field-magnet B, and C is the motor-armature journaled to rotate Specicatiion of Letters Patent. Patented J 22, 1919, Application med october 5, 1917. serial No. 194,849.v i

between the eld-ma net-poles. VThe motor is preferably of the ipolar type. The up; per end of the casing A is closed by a cap D which affords a bearing for the armature shaft and also contains the commutatorbrushes or contacts E of the motoras apcasing A is closed by a disk F in which the other4 end of the armature shaft is journaled. A" represents a second section of casing having a screw-joint connection with the section A and containing the hammer portion of the apparatus.- A fan G is provided at the left-hand end of the motor and ventilatingopenings a a are formed in?, the shell A through which air may be drawn by the fanfor cooling the apparatus.

The reduced portion of the shell A carries the actuating spring K which is coiled around the shaftvof thehammer H concenpears in Fig. 6. VThe opposite end of the trically therewith. Anut h is screwed on.' the lower end of the hammer serving as an abutment-for one end of the spring K and also as a means for adjusting the spring tension. Openings H in the n ut k provide for the fiow of air within the casing section and for the admission of air which will be drawn up through the tool through suitable ducts by means of the fan G. The u per end of the hammer-element, or striker is rovided with a squaredv portion iH4 w ich passes through a square hole in the disk L to prevent itsfrotation and also with a cylmdrical head H2 that carries the rollers J. A disk L1, having a central cylindrical extension L2 which-surrounds the striker H 1s seated against a shoulder in the casing A -and the aforesaid disk L, is seated against the disk L1, both disks being kept from turning within the shell by 'a pin Z. The upper VI and is of an annular form surroundn the hammer and mounted to rotateon the alle grooved to form a Vforming. the thrust bearing aforesaid. The

inclined surfaces of the cam are shown as forminga'series of saw tooth or ratchettoothpoints indicated at p1 and p2. In the illustrated machine there are three of these tool are t points equally spaced apart around the circumference ofthe cam. They form maximum points for the cam and coperate with three -iollers J projecting radially from the lenlarged head H2 of the hammer. By means of such a plurality of maximum lifting points on the camfthe lifting strain is substantially symmetrical with respect to the axis of the hammer and side thrust on the hammeris avoided. The cam P is connected with a hollow cylinder, or sleeve, R which is provided near its upper end with internal gear teeth S. The internal g'ear, as appears more clearly in Fig. 4l,y meshes with idler pinions S1 which, in turn, mesh with al gear S2 on the motor shaft. Thel inions S1 are mounted on studs proj ecting rom the under side of the aforesaid disk F which pertains to the shell A. Thus by unscrewing the joint between the casing sections A and A the tool may be separted, the pinions S together with the motor and the pinion S2 goin with the part A, while the internal gear goes with the plart A. When the two parts of the us separated, the hammerelement together with the cam and the spring may l be lifted out through the open end of the section A. Then by' unscrewing nut h, the

L hammer, the cam and the spring may be takeny apart. `That is, the three parts just' tion A.

mentioned form a unitary structure which can be 'inserted as a whole in the casing-secmotor rotates the drivin pinion S1, acting through the idlers S wil rotate the cylinder or sleeve R together with the cam P. The lifting points of the cam will act periodically to raise the hammer and compress the spring K, the hammer being prevented from rotating by means of the squared portion H. When the rollers drop off the lifted points of the cam, the spring will be released and will force the descent of the hamp mer to give the impact or blow of the hamdescribed.l The sleeve and gears form a driving-connection, between lthe armature shaft and the cam, which extends around or outside of the rollers J- which form the extensions from the hammer that en age and travel u on the workin surfaces o thecam.

The e ectric motor w en'of the D. C; type has its field magnet and its armature se- It will be manifest that when thel ries in order to give the periodic torque-impulses required to lift the hammer against the aforesaid spring. The vvmotor is con-4 trolled byl a simple switch W and is located in. the handle of the tool, bein operated by a push button W1 which proJects through the side of the handle.

What we claim as new and desire togsecuie by Letters Patent is:

1. An automatic hammer comprising a striker, an'actuatin spring therefor, an electric motor, an annu ar lifting cam surrounding the hammer and engaging the spring, ex-

tensions on the hammer engaging said cam and a driving connection between the motor and the cam passing outside ofsaid exten sions.

2. An automatic hammer comprising a striker, an actuating spring therefor, an electric motor having its shaft in line with said striker, an annular lifting-cam surrounding the hammer, an extension on'the hammer engaging said cam and a driving connection between the motor-shaft and cam which passes outsideof said extension.

3. An automatic hammer comprising a striker and an actuating spring therefor, an

electric motor having its shaft in line with said striker, an annular lifting-cam surrounding the hammer, an extension on the hammer engaging the said cam,` and a'gear- "connection between the motor-shaft and cam which passes outside, of said extension.

4. An automatic hammer comprising a striker and an actuating-springtherefor, .an electric motor having its shaft in line with said striker, an annular lifting-cam surrounding thehammer and acting on the spring, a cam-gear connected to t e inion on the motor-shaft and a gear wheel between said pinion and said cam-gear.

cam, a

5. An automatic hammer comprising astriker and an actuating. spring therefor concentric with the striker, and an electric motor having its shaft in line. with the striker, a cam device for tensionino' and releasing the spring located between the spring and the motor, and a driving connection between said cam-deviceaml the motor.

6. An automatic hammer comprising a striker, an actuating spring in the lower part ofl the hammer concentric with the striker, lan electric motor in the upper part of the hammer an intermediate annular cam acting on the spring, and a driving connection external to the cam between the cam and the motor. v

7 An automatic hammer comprising a reciprocating striker and an actuatingspring therefor, an annular cam loosely engagin the striker, rollers carried by'the'strker an positioned to engage the working face .of the cam, means for .preventing rotation of the striker, a friction-roller thrust-bearing'- for the cani, an electric fmotor, and a gear iso 9. An automatic hammer comprising a rereciprocating striker, an actuating spring therefor, a casing extendingl longitudinally of the said striker, an electric motor having its shaft in line with the striker, a cam device driven by the motor independently of the striker and operating transversely to the axis of the striker, and means on the striker cooperating with said cam to periodically tension and release' the spring.

10. An automatic hammer comprising a reciprocating striker, an actuating spring therefor, an electric motor, an intermediate cam driven by the motor to periodically tenv sion and release the spring, and a longitudinal casing one detachable section of which serves as a part ofthe magnetic circuit of the motor 'and is provided with motor bearings while the other section receives the reciprocating striker, the spring and the spring-actuating.A cam.

` 11. An automatic hammer comprising a striker, an actuating spring therefor, an

electric motor, a cam driven by the motorv to periodically tension and release the spring, and an inclosing casing, the springbeing held between abutments which are removable bodily from the casing together withthe spring.I

12. An automatic hammer comprising a striker, an actuating spring therefor, an electric motor, a cam driven by the motor to periodically tension and release 4the spring, a casin members on the striker between which t e spring is held undern tenthe casing and detachable from the remainsion, the striker together with said members and-the spring being bodily removable from ing mechanism, a stop on the striker against which one end of the spring abuts, an annular cam, an extension on the striker bearing on the working surface of said cam and `held thereon by `the tension of the spring and a bearing for the cam sustained by the Y casing.

13. An automatic hammer comprising a reciprocating strikernd an actuating spring therefor, an annular spring-tensioning cam surrounding and loosely engaging the striker, said cam having maximum points on opposite sides of the striker axis, and an electric motor operatively connected with said cam to rotate thevsame.

14. An automatic hammer comprising a. reciprocating striker, and anY actuating spring therefor, an electric motor, a casing,

a transverse member in the casing through which the striker reciprocates, a cam loosely engaging said striker and rotatably engaging said transverse member through Y an interposed thrust-bearing, rollers on the striker traveling upon the working surface 'of said cam and a driving connection between said cam andthe motor, whereby thev cam is rotated.

l5. An automatic hammer, comprising a reciprocating striker, a spring surrounding the striker, a cam mounted to rotate independently of the striker, means on the striker coperating with said cam :toralter-` nately tensioning and releasing vthe spring, an electric motor and a two-step gear operatively connecting said cam and motor.

r16. An automatic hammer comprising in combination 1a two-part cylindrical casing one part containing an electric motor having its shaft extending longitudinally of the casing and provided with a handle for the hammer, the other part being in line with the irst part and containing a reciprocating striker, an actuating spring therefor abuttingat one end on the casing and at the other end on the striker, a cam for alternately tensioning and releasing the spring,

and a separable driving connection between said cam and the shaft of the motor.

Signedthis 25th da of Se tember, 1917. GEOR EL. OLLOCK.

ROBERT P. MARTIN. 

